Back to results
US 4,991,054 AGranted
Time-delay outdoor lighting control systems
AssigneePacific Scientific Company
InventorJeff Walters
Life of this patent
Estimating the term…
Abstract
An optical lighting control, such as that used to control street lamps, delays the response of the lamps to changes of illumination while the lamps are on at night but avoids the delay in response to daylight. Thus, headlamps, flashlights, and lightning flashes of brief duration do not cause the control to turn off the street lamps. However, the street lights turn off without this delay in response to daylight.
Claims34
A control, comprising:
- a switch for use in an electric line;
- operating means for operating said switch and responsive to ambient light in a first light range at a slower rate than to ambient light in a second light range dimmer then the first light range and ambient light in a third light range brighter than the first light range.
A lighting system comprising:
- a power source;
- a plurality of power lines;
- a lamp;
- and
- an outdoor lighting control,
- said outdoor lighting control including a switch in one of said lines;
- said outdoor lighting control further including operating means coupled to said switch for responding to ambient light in a first light range at a slower rate than to ambient light in a second light range dimmer than the first light range and ambient light in a third light range brighter than the first light range.
4 more elements
A control, comprising:
- a switch for switching an electric line on and off;
- operating means coupled to said switch and sensitive to incident light striking said operating means for operating said switch at a slower rate in response to rising incident light than in response to declining incident light.
A lighting system, comprising:
- a power source;
- a power line;
- a lamp in said power line;
- and
- an outdoor lighting control coupled to said power line;
- said outdoor lighting control including a switch in said power line;
- said outdoor lighting control further including operating means coupled to said switch and sensitive to incident light striking the operating means for operating said switch at a slower rate in response to rising incident light than in response to declining incident light.
4 more elements
Dependencies are inferred from the claim text.